Thickened nitroparaffin containing stabilizer



United States Patent Ofiice 3,3183% Patented May 8, ldd? 3,318,741 Tli-lllCKENED NITRUPARAFFHN CGNTAINING STABHLIZER Lawrence R. Jones, Terre Haute, lind., assignor to Commercial Solvents Corporation, New York, N.Y., a corporation of Maryland No Drawing. Filed Apr. 8, 1965, Ser. No. 446,736 8 Claims. (Cl. 149-89) This invention relates to nitroparailin-containing compositions. In a particular aspect it relates to gelled or thickened normally liquid nitroparafiin compositions. In a further aspect it relates to gelled or thickened normally liquid nitroparafiin compositions stabilized against liquefaction.

Liquid nitroparaffins, such as nitromethane and nitroethane, are used as propellants in jet propulsion devices and in explosives. It is desirable in some cases to employ the normally liquid nitroparaifins in a gelled or thickened form. It is also often desirable that these gelled or thickened forms of nitroparaffin compositions be stabilized against liquefaction for extended periods of time.

It is an object of the present invention to provide gelled or thickened normally liquid nitroparaffins, particularly nitromethane and nitroethane.

It is a further object of the present invention to pnovide gelled or thickened nitroparaffins, particularly nitromethane and nitroethane which are stabilized against liquefaction over extended periods of time.

It is a still further object of the present invention to provide a method for gelling or thickening normally liquid nitroparaflins, particularly nitromethane and nitroethane.

It is an additional object of the present invention to provide a method for stabilizing gelled or thickened normally liquid nitroparaflins, particularly nitromethane and nitroethane.

Other objects and advantages of the present invention will be apparent from the specification and the appended claims.

The present invention in a first embodiment resides in the discovery that a nitroparaffin selected from the group consisting of nitromethane and nitroethane and mixtures thereof is converted from its normally liquid form to thickened compositions having viscosities ranging from syrupy liquids to rigid gels by incorporating therewith high molecular weight polyoxyethylene.

The present invention in a second embodiment resides in the discovery that thickened compositions of a nitroparafl'ln selected fnom the group consisting of nitromethane and nitroethane and high molecular weight polyoxyethylene are made stable against liquefaction for extended periods of time by the inclusion therein of poly- (methylvinylether/maleic anhydride).

The polyoxyethylene of use in the present invention is of high molecular weight. Specifically, the average molecular weight is in the range of about one hundred thousand to about five million. The high molecular weight polyoxyethylene is obtained by the polymerization of ethylene oxide. These polymers are commercially available.

The poly(methylvinylether/maleic anhydride) compounds of use in the present invention are copolymers of methylvinylether and maleic anhydride. These copolymers are also commercially available.

The compositions of the present invention are obtained by adding the high molecular weight polyoxyethylene to the liquid nitroparaifin at temperatures and under pressures at which explosion of the nitroparafiin is avoided. Room temperature and atmospheric pressure are conveniently employed. The poly(methylvinylether/maleic anhydride) may be separately added to the nitroparafiin either before or after addition of the high molecular weight polyoxyethylene or it may be added as a mixture with the high molecular weight polyoxyethylene.

The ratio of nitroparafiin to high molecular weight polyoxyethylene may be varied in order to obtain the particular desired compositions. A trace of polyoxyethylene has a thickening effect on the nitroparaffin with which it is employed. A fairly thick nitroparaflin composition is formed by incorporating in the nitroparafiin as low as about 0.5 percent by weight of polyoxyethylene the weight based on the nitroparaflin. Reasonably rigid gels are formed when about 1 to about 5 percent by weight of polyoxyethylene is employed. Particularly stiff gels are obtained by use of amounts of polyoxyethylene in excess of 5 percent by weight. The amount of polyoxyethylene which may be incorporated in the nitroparaffin composition by stirring alone does not appreciably exceed 10 percent by weight based on the weight of the nitroparatfin. If it is desired to obtain homogeneous mixtures of nitroparaflin and polyoxyethylene containing in excess of 10 percent by weight of polyoxyethylene, it is preferable to mill or knead the mixtures.

The ratio of nitroparaflin to poly(methylvinylether/ maleic anhydride) also may vary. A trace of poly(methylvinylether/maleic anhydride) has a stabilizing effect on compositions of nitroparafiin and polyoxyethylene. Generally it is preferred to use from about 0.1 to about 5.0% by weight of poly(methylvinylether/maleic anhydride) based on the weight of the nitroparaifin. While amounts greater than 5 percent poly(methylvinylether/maleic anhydride) may be employed such amounts are considered excess.

The above described compositions may be employed as propellants or in explosive compositions. However it is sometimes desirable to incorporate one or more additives into the compositions in order to alter or enhance their performance in a particular application. For example, when the compositions are used as explosives, it is often desirable to incorporate therewith a sensitizer or a desensitizer. When the compositions are used as propellants, additives such as fuel components, oxidizers and burning catalysts may be utilized.

Examples of sensitizers include the aromatic amines such as aniline, diphenylet-hylene diamine and the like; and the aliphatic amines such as diethylamine, tetraethylene pentamine and the like.

Examples of desensitizers include benzene, 1,2-butylene oxide, acetone, cyclohexane, 1,4-dioxane, l-nitropropane, methanol, Z-nitropropane, methylene chloride, and methyl chloroform.

Examples of fuel components include elemental carbon in various forms such as carbon black, graphite, and the like; aliphatic hydrocarbons such as pentane, octane, dodecane, cyclohexane and other cyclic parafilns; organic polymers such as liquid and solid polymers of ethylene and propylene; organic ketones such as diethylketone, ethyl butyl ketone, dihexylketone, cyclohexanone, methylphenyl ketone and the like; and alkyl ethers of saturated glycols such as monomethylether of ethylene glycol and monoethylether of ethylene glycol and the like.

Examples of oxidizers include solid organic oxidizers such as guanidine nitrate, pentaerythritol tetranitrate, cyclotrimethylene trinitramine and the like; and solid inorganic oxidizers such as ammonium nitrate, lithium nitrate and the like.

Examples of burning rate catalysts include chrome acetyl acetonate, ammonium chromate, iron oxide and the like.

The invention will be understood more fully by reference to the following specific examples. It is understood that the examples are presented for the purpose of illustration only and are not intended as a limitation of the invention.

Examples 1-6 inclusive are offered to illustrate the 4 stand at room temperature for thirty days. At the end of the thirty-day period no signs of liquefaction of the gel were observed.

Additional examples of stabilized compositions of nitroabillty high molecular Weight p y y y to form 5 parafiins, high molecular weight polyoxyethylene and polythickened compositions with normally liquid nitroparaflins. (methylvinylether/maleic anhydride) are given in Tabl 2. In Example a copolymer of methylvinylether and Example 1 maleic anhydride manufactured by General Aniline and A rigid gel was prepared by mixing 97 parts by weight Film Corporation and commercially sold under the name of nitromethane and 3 parts by weight of a high molecular 10 GantreZ-1l9 is used. In Example 11 a copolymer of weight polyoxyethylene manufactured by Union Carbide methylvinylether and maleic anhydride manufactured by Corporation and commercially sold under the name General Aniline and Film Corporation and commercially Polyox WSR301. The gel was allowed t stand at room sold under the name Gantrez-l69 is used. The compositemperature for one week. At the end of the one-week tions were prepared following the procedure of Example 7. period a small amount of liquefaction of the gel had 15 The compositions were found to be stable against liqueoceurred. faction.

TABLE 2 Example Nitroparaflin Parts by Gelling Agent Parts by Stabilizing Agent Parts by Weight Weight Weight Nitromethane 98 High molecular Weight polyoxyeth- 1 Poly(methylvinylether/maleic l ylene (Polyox WSR-301). anhydride) (Gantrez-l). Nitroethane 98 .d0 1 do l Nitromethane.. 97 .d0 2.5 Poly(methylvinylcther/maloic 0.5

anhydride) (Gantrez-lltl). 11 d0 95 do 2.5 Poly(methylvinylether/maleic 1.5

anhydride) tGantrez-lti Additional examples of compositions of nitroparafiins Since many embodiments of this invention and since and high molecular weight polyoxyethylene aregiven in 30 many changes may be made in the embodiments described, Table 1. In Example 3 a high molecular weight polythe foregoing is to be interpreted as illustrative only and oxyethylene manufactured by Union Carbide Corporation the invention is defined by the claims appended hereto. and sold under the name Polyox Coagulant is used. In I claim:

Example 5 a high molecular weight polyoxyethylene 1. A composition of matter comprising a nitroparaifin manufactured by Union Carbide Corporation and sold selected from the group consisting of nitromethane and under the name of Polyox WSR-205 is utilized. In Exnitroethane and polyoxyethylene having a molecular ample 6 a high molecular weight polyoxyethylene manuweight of at least 100,000, said polyoxyethylene being f actured by Union Carbide Corporation and sold under present in amounts effective to thicken the nitroparafiin. the name Polyox WSR-35 is used. The compositions 2. The composition of claim 1 wherein the composition were prepared following the procedure of Example 1 and contains from about 0.5 to about 10 percent by weight were found to have stability similar to the composition of polyoxyethylene based on the weight of the nitroparof Example 1. :ai'fin.

TABLE 1 3. The composition of claim 1 wherein the composition contains from about 1.0 to about 5.0 percent by weight Parts Parts of polyoxyethylene based on the weight of the nitropar- Example Nitroparafiln by Gelling Agent b y aflin,

Welght fight 4. A gelled or thickened normally liquid composition comprising a nitroparaffin selected from the group con- 2 Nltmmethanem 98 .3 2 sisting of nitromethane and nitroethane, polyoxyethylene gg g gigsrolyox having a molecular weight of at least 100,000, and poly- 3 "do H 97 High molecu'lar 3 (methylvinylether/maleic anhydride), the said poly(methgiggl ggg ggg ylvinylether/maleic anhydride) being present in amounts 0039mm) effective to stabilize the composition. 4 Nitroethanenm 96 fligllmolecularg 4 5. The composition of claim 4 wherein the polyoxyweight polyoxyethylene (Polyox ethylene is present in amounts rangmg from about 0.5 to 5 Nitromethane 92 ggg gg 8 abo t 10 percent by weight based on the weight of the weight DOWOXY. n1troparaflin. %E 6. The composition of claim 5 wherein the poly(meth 6 90 ansas. 10 apat te 3 ,3 3 g gi gfi y a a g s ess s e cen y eig ase ii iiiggf on the weight of the nitroparaflin.

7. A method for gelling or thickening a nitroparafiin Examples 7-11 inclusive are offered to illustrated the sejlected from h grOuP Fonsisting of nitfomethane and ability of poly(methylvinylether/maleic anhydride) t nltroethane WhlCl'l comprises incorporating in the nitrostabilize thickened nitroparaffin compositions. 5 Paraffil'l from about to about 10 Percent y Weight of polyoxyethylene having a molecular weight of at least Example 7 100,000, the weight percent based on the weight of the A rigid gel was prepared by mixing 97 parts by weight nitfopal'flffinof nitromethane, 2 parts by weight of high molecular 8. A method for stabilizing gelled or thickened nitroweight polyoxyethylene manufactured by Union Carbide paraflins selected from the group consisting of nitrometh- Corporation and commercially sold under the name Polyox WSR-301 and 1 part by weight of poly(methylvinylether/maleic anhydride) manufactured by General Aniline and Film Corporation and commercially sold under the name Gantrez-l39. The gel was allowed to ane and nitroethane which comprises incorporating from about 0.1 to about 5.0 percent by weight of poly(methylvinylether/maleic anhydride) into a composition comprising a nitroparaffin and from about 0.5 to about 10 percent by weight of polyoxyethylene having a molecular weight nitroparafiin.

References Cited by the Examiner UNITED STATES PATENTS GoW et a1 149-93 X Schaad 14989 FOX 149-89 X 6 Wilson 14989 X Merges 149109 Doyle 14919 X Atkins et a1 149-89 Egly et a1 14989 X CARL D. QUARFORTH, Primary Examiner.

BENJAMIN R. PADGETT, Examiner. Long 149-89 X 10 S. J. LECHERT, JR., Assistant Examiner. 

1. A COMPOSITION OF MATTER COMPRISING A NITROPARAFFIN SELECTED FROM THE GROUP CONSISTING OF NITROMETHANE AND NITROETHANE AND POLYOXYETHYLENE HAVING A MOLECULAR WEIGHT OF AT LEAST 100,000, SAID POLYOXYETHYLENE BEING PRESENT IN AMOUNTS EFFECTIVE TO THICKEN THE NITROPARAFFIN.
 4. A GELLED OR THICKENED NORMALLY LIQUID COMPOSITON COMPRISING A NITROPARAFFIN SELECTED FROM THE GROUP CONSISTING OF NITROMETHANE AND NITROETHANE, POLYOXYETHYLENE HAVING AMOLECULAR WEIGHT OF AT LEAST 100,000, AND POLY/ (METHYLVINYLETHER/MALEIC ANHYDRIDE), THE SAID POLY(METHYLVINYLETHER/MALEIC ANHYDRIDE) BEING PRESENT IN AMOUNTS EFFECTIVE TO STABLIZE THE COMPOSITION. 